Mostly based on patches provided by Hallvard B. Furuseth

ITS#1677 - cast away const warnings
ITS#1678 - unsigned char args to ctype funcs
ITS#1682 - don't redefine ldap_debug
ITS#1683 - uninitialized vars
ITS#1703 - ldo_debug initialization
ITS#1705 - unsigned testing
ITS#1706 - socklen_t args
ITS#1719 - back-tcl update (other cleanups/fixes/improvements; yet untested)
ITS#1724 - integerNormalize/integerFilter/integerIndexer bugs
ITS#1725 - libdes not required

Implement back-null (/dev/null style backend)
Cleanup some misc warnings ("%lu" format, unused/uninitialized vars,
        ambiguous operator precedence)

Kurt, please regenerate configure